A new remote operations center on the west side of the Wilson Hall atrium will house detector operations for the lab's neutrino and muon experiments. Image: FESS

Construction work for the new remote operations center begins today. This work, on the atrium level of Wilson Hall, will require the closing of portions of the west stairway. Access from the ground floor, atrium level and second floor of the stairway will be blocked for the duration of the construction activities. Access above the second floor will be maintained.

The new remote operations center will serve as a hub for scientists on Fermilab's neutrino and muon experiments. They will use the new facility for experiment operations, similar to scientists using the LHC Remote Operations Center on the east side of the atrium for the CMS experiment.

From symmetry

Start spreading the SNEWS

A worldwide network keeps astronomers and physicists ready for the next nearby supernova. Photo courtesy of NASA

When it comes to studying supernovae, if you don't SNEWS, you lose.

SNEWS, the Supernova Early Warning System, is a worldwide network designed to do just what the name implies: let astronomers and physicists know when a nearby supernova appears. This can be a tricky business, since supernovae appear in our galaxy roughly once every 30 years, and the window for studying them can vary — anywhere from a few weeks down to a few hours.

Seeing a supernova in action is certainly a great chance to learn about how supernovae work. But it's the burst of neutrinos released in a supernova that most interests Kate Scholberg and Alec Habig, the two physicists who spearheaded SNEWS. Scholberg and Habig were postdoctoral researchers on the Super-Kamiokande neutrino experiment when the idea was first discussed in the late 1990s.

"There is enormous potential to learn about neutrinos from supernovae," says Scholberg, now a professor at Duke University. "We can learn about their properties, like their mass, their ability to oscillate and potentially exotic effects. Furthermore, with supernova neutrinos, we get the complete story of the stellar core collapse, a story that is of great interest to a lot of theorists."

The trick is to catch them. Neutrinos are the most abundant particles in the universe, and physicists know very little about them. That's because they're notoriously elusive — they rarely interact with matter and have miniscule masses. Terrestrial neutrino experiments fire billions of the tiny particles at massive detectors every few seconds and see only a few interactions a week.

Supernova neutrinos are even more difficult to pin down. As Habig, now a professor at the University of Minnesota, Duluth, explains, neutrinos are often the first sign of a supernova, arriving before anyone knows what's happening.

"You get the neutrinos before you get the light," Habig says. "It takes hours before you see the photons. Depending on the type of star, it could take up to 12 hours for the photons to blast their way out of the dying star, but the neutrinos escape immediately."

It's that very principle that allows SNEWS to work. It starts with five of the biggest neutrino experiments in the world: Super-Kamiokande and KamLAND in Japan, the Large Volume Detector and Borexino in Italy, and IceCube in Antarctica. Each experiment can detect supernova neutrinos.

Once potential supernova neutrinos are detected in one of these experiments, a datagram is sent to the SNEWS computer, housed at Brookhaven National Laboratory in New York. If multiple datagrams indicate that two bursts of neutrinos arrived within ten seconds of each other, the computer automatically alerts the SNEWS mailing list. According to Habig, there are nearly 2,700 email addresses on the list, although some of those addresses send to lists themselves. (Sky & Telescope magazine's AstroAlert list receives SNEWS alerts, for example.)

Check your privilege with an antimatter beam

From The Guardian, March 1, 2014

In a sense, antimatter beams are commonplace. The Tevatron machine at Fermilab in Chicago had the best beam of antiprotons, and used it to find the top quark. The LEP collider, which between 1990 and 2000 sat in the tunnel at CERN now occupied by the Large Hadron Collider, had a beam of positrons — the antiparticle of the electron. However, proper matter, everyday matter, is made of atoms. That is, electrons bound to an atomic nucleus. Slowing positrons and antiprotons down and making them stick together into anti-atoms of antihydrogen is difficult.

The dangers of laser "toys"

Both of these laser pointers look the same, but only one of them meets the 5-milliwatt-maximum requirement. Photo: ESH&Q

A recent Nature paper describes the cases of five children in the UK who received eye injuries as a result of playing with laser "toys." These children, between the ages of eight and 15, suffered reduced vision and had identifiable damage to their retinas. All reported playing with these so-called toys before their eye problems began.

In the United States, the FDA regulates laser devices, including laser pointers. Laser pointers should be labeled with the correct output power and class. Handheld lasers of any color, or wavelength, that have a power output of greater than 5 milliwatts can pose significant eye hazards and should not be used, especially by children.

Unfortunately, anyone can buy a laser that exceeds 5 mW and believe he or she is getting an FDA-compliant laser pointer. The higher-power devices look like and can be priced like laser pointers. It is easy to find a 50-mW green laser on the Internet for $10. Many times these lasers are incorrectly labeled and emit more power than their label indicates.

At Fermilab, we require that laser pointers be less than 5mW (Class 3a or 3R) and suggest that they be less than 1 mW (Class 2). The Fermilab Stockroom stocks Class 2 red laser pointers that have been approved by the ESH&Q Section; the stock number is 1375-2300. As Fermilab's laser safety officer, I am also available to measure the power of any laser pointers.

Outside of the lab, you should be cautious when buying or using a laser pointer. Here are some ways to choose an appropriate laser pointer and avoid eye injuries:

Purchase products only from reputable vendors to ensure the quality of the product.

Read manufacturer specifications to make sure you are purchasing a product with the proper output.

Purchase only lasers below 5 mW and labeled as Class 1, 2, 3a or 3R.

Do not stare into the beam.

Ensure children are supervised by an adult when using laser pointers.

Do not point the beam at people or shiny objects. The reflection can cause damage.

Do not point a laser at aircraft of any kind. It is a federal crime.

If you have any questions about laser safety, I'm here to help. Contact me at mquinn@fnal.gov or at x5175.

—Matt Quinn, laser safety officer

Photo of the Day

Wading in the winter pool

Birds of different feathers wade through the cold water near the Main Injector. Photo: Marty Murphy, AD

In the News

Synopsis: No quantum black holes detected at LHC

From Physics, March 5, 2014

We have gotten used to Einstein's representation of spacetime, in which space and time are interwoven into a four-dimensional continuum. But according to certain quantum gravity theories, there may be some extra, hidden dimensions of space, curled up on a scale much smaller than a proton. In this case, theoretical calculations have suggested the Large Hadron Collider (LHC) could produce ephemeral objects called quantum black holes (QBHs) as it smashes particles together. Quantum-mechanical effects play an important role in these objects, making them decay instantly with no macroscopic consequences. The observation of such QBHs would thus call for a revision of our understanding of spacetime.